中国沙尘暴时空变化特征及日本、韩国黄沙的源地研究

利用1961～2000年中国681个站的气象实测资料,分析了近40年我国沙尘暴月际时空分布特征.结果表明,中国沙尘暴主要发生区域在青藏高原和北方干旱半干旱地区.12～3月,沙尘暴发生中心集中在青藏高原上,并随时间推移中心向北推移;4～6月在北方的干旱半干旱地区,其中4月是中国沙尘暴发生范围最大的月份;对比中国沙尘暴和日韩黄沙天气的月际分布,推测日韩两国冬季的黄沙大部分应该来源于青藏高原,春季青藏高原也有一定的贡献.由于沙尘暴发生在相差悬殊的不同海拔高度上,特别是在春季,扬起的沙尘在低层随涡旋系统而高层随行星西风向下游传输,可能是日韩观测到沙尘多层结构的重要原因之一.

Monthly Temporal-Spatial Distribution of Sandstorms in China as Well as the Origin of Kosa in Japan and Korea

Based on the available observation data from 681 meteorological stations in China during 1961-2000,the monthly temporal-spatial distribution of sandstorms indicates that sandstorms occur most frequently in the Tibetan Plateau(Qinghai-Xizang Plateau)and the arid and semi-arid areas in northern China. The center of sandstorms is in the Tibetan Plateau and gradually moves northward from December to March, however the center is in northern China during April to June and the most areas of sandstorms happen in April. Contrast of the monthly temporal-spatial distributions of sandstorms among China,Japan, and Korea shows that, in winter and spring, the majority of KOSA(yellow sand) in Japan, and Korea derive from the Tibetan Plateau and northern China respectively. And part of KOSA comes from the Qiangtang Plateau in spring as well. Sandstorms occur in different altitudes between the Tibetan Plateau and northern China, especially in springtime, the dust is transported by the vortex system in lower levels and by the planet westerlies in upper levels, which is one of the main causes of multi-layer structure of KOSA in Japan and Korea.